1) Clinical symptom complex characterized by presence of multiple cysts on the ovaries, oligomenorrhea or amenorrhea, anovulation and regularly associated with excessive amounts of body hair (hirsuitism), excessive body weight, infertility and insulin resistance.

2) A variable disorder that is marked especially by amenorrhea, hirsutism, obesity, infertility, and ovarian enlargement and is usually initiated by an elevated level of luteinizing hormone, androgen, or estrogen which results in an abnormal cycle of gonadotropin release by the pituitary gland -- abbreviation PCOS; called also polycystic ovarian disease, polycystic ovarian syndrome, polycystic ovary disease, Stein-Leventhal syndrome.